Identical or Non-Identical Twins?

When John and Liz O’Neill were told they were going to have twins they were over the moon. During their scans they found out the twins were developing inside separate amniotic sacs, and as a result were told by the medical staff they would be non-identical.

The adorable Oscar and Oliver were born on 9th February 2012. Both parents were understandably smitten, but also amazed at how alike the tiny siblings were.

Over the next 12 months Liz and John were constantly stopped in the street or the supermarket where strangers would coo over the twins and say ‘they must be identical!’ Although they would explain no, they were actually non-identical, the twins striking similarity meant they themselves had always harboured some doubt.

Shortly after the boys 1st birthday, while reading an article on twins, Liz discovered that it was actually possible for identical twins to develop in separate sacs if the egg splits very early on during development. With this new information and a sneaking suspicion that their initial instincts had always been right, Liz contacted us at PlayDNA to ask for help.

“I went to school with Sam, and knew through facebook that she had started a business creating DNA artwork with meaning. I thought her forensic artwork might offer some clue as to whether Ozzy and Olly were identical or not” said Liz. We agreed to help, and took samples of DNA from each family member, including the twins older brothers Jack, age 8 and Josh, age 5.

“When I saw the photos of Oliver and Oscar I too had assumed they must be identical” says Dr Sam. “I thought it would be a wonderful project to have a peek inside their genes and see what that told us about their story, and also make a wonderful family memento!”

Dr Sam prepared a bespoke piece of artwork for the family, which looked at ten different genes related to particular traits, such as eye colour, memory and whether you’re more likely to be an early bird or night owl. The results were pretty conclusive.

“Olly and Ozzy shared all ten genes in common – which combined with their amazing likeness is a sure sign that they are actually identical twins!” says Dr Sam. “This is made more apparent when we see their DNA portraits alongside their elder brothers, who very obviously have several differences in their DNA. We calculated the odds of them sharing these genes by coincidence, and it works out at 0.39% - in other words, less than a 1 in 200 chance. The O’Neill family now has their colourful DNA portraits framed and on the wall for all to see.

Mum Liz told us: “Thank you so much for taking the time to explain what it all means despite being so busy. We really appreciate it. It was so interesting and is all we've talked about since. We've named ourselves team night owl and are putting together our owl names and power rangers style salute! The kids are loving it. We're so excited about having the artwork in the house and being able to explain it properly to all our family and friends. It's a brilliant thing for the kids to be able to grow up around and learn from. I just wanted to let you know how grateful we are”.